Bobbin



1941- I J. A. KENNEDY BOBBIN Filed Dec.

3 y p// fi/ 7////// 7//// 7 INVENTOR ATTORNEY.

Patented Mar. 25, 1941 UNITED STATES BOBBIN John A. Kennedy, Saco, Maine, asslgnor to vSacc- Lowell Shops, Boston, Mass., a corporation of Maine Application December 19,1938, Serial No. 246,539 v -2 Claims. (01. 242-120) This invention relates to-bobbins such as those used in spinning, twisting and other textile machines. bobbins themselves and also their mounting on 5 the spindles which support and drive them.

In recent years there has been a constant trend toward the use of larger packages and higher speeds in spinning, twisting, and similar operations. The increased package size is of advantage 10 in permitting longer production runs between shut-downs for dofling, while a higher spindle speed means, other conditions being equal, a greater production per operating hour. This trend has progressed to a point where the pack- 15 age load and the rotative speed in many cases introduce difficulties which offset some of the advantages gained, and one of these is the greatly increased rate of wear of both the bobbins and spindles, particularly at the points where the v '20 two are in mutual contact.

It is the common practice so to mount'bobbins upon their supporting spindles that the wall of the enlarged bore at the base of the bobbin is pressed down upon and maintains a driving fit 25 in a circumferential Iineof contact with the tapered portion of the spindle, commonly termed the acorn. The spindle blade projects upwardly from this acorn and is much smaller in diameter so that there is no contact between the bobv bin and any part of the spindle above the acorn up to a point near the tip or nose of the bobbin where its bore is reduced in size sufficiently to en- I gage the spindle blade and thus center the bobbin. However, the common practice is to maintain a 5 clearance of a few thousandths of an inch between the blade and the bore of the bobbin at this point. I Such a construction is considered necessary to permit the bobbin to be seated with a driving fit on the tapered acorn, since otherwise 0 the blade, which often also is tapered nearits upper end, might first engage the bobbin and so prevent the production of efie'ctive driving contact between the bobbin base and the acorn. In addition, some clearance between the bobbin tip and the blade is of advantage in producing better running conditions.

While such constructions have been successful heretofore, the use of higher speeds and larger and heavier yarn packages, coupled with the fact that such packages are never accurately balanced, has so increased the vibration and torque loading upon the spindle that the rate of wear of the parts has been greatly increased and has become an important practical factor. Frequently a slippage occurs between the bobbin and the It involves both the construction of the I spindle, due to several causes, such as the increased drag of the traveler, or the vibration of the bobbin, with a resulting tendency of the bobbin to chatter. Often, also, vibration of the bobbin whips the upper end'of this member against 5 the blade of the spindle, producing wear which increases very rapidly with an increase in the amplitude of relative oscillation of the parts. This also tends to loosen the driving engagement of the bobbin with the acorn.

The present invention aims to improve bobbins with a view to avoiding the difficulties above described.

The nature of the invention will be readily understood from the following description when read in connection with the accompanying drawing, and the novel features will be particularly pointed out in the appended claims.

In the dra 'ng,

Figure 1 is a vertical, sectional view of a bobbin embodying features of this invention and shows the bobbin mounted in its operative position on a spindle;

Fig. 2' is a similar view of a modification; and

Fig. 3 is a plan view of the split ring shown in Figs. 1 and 2. v

Referring firstto Fig. 1, the construction there shown comprises a spindle of a common ;form including a blade 2, a whirl 3 and an acorn l. Mounted on this spindle is a bobbin 5 comprising a hollow or tubular body, similar in its general form to the bobbins commonly used. It may be made of wood, in accordance with the usual custorn, or of any other suitable material. The bore of the base portion of the bobbin is tapered to conform to the taper of the acorn 4 and thus to produce a good driving fit between these parts. In this respect the construction shown is a departure from the usual practice.

The upper portion of the bobbin differs very radically from prior constructions in that it is equipped internally with a resilient bushing 6 made of rubber, cork, or equivalent materials,

rubber of either the common or synthetic forms being preferred. This bushing is held in a fixed position longitudinally of the bobbin and its bore is made very slightly larger, say one-thousandth or two-thousandths of an inch, than the outside diameter of the spindle, so that the bobbin may be readily slipped on and off the spindle. Because of the resilient nature of the material of which the'bushing is made it serves to yieldingly center the upper portion of the bushing on the spindle blade. It provides a yielding surface for engagement with the blade which prevents any chatter of the bobbin, while at the same time having such a degree of durability that wear of the mutually contacting surfaces of the bushing and blade proceeds at an extremely low rate.

It is important to be able to install and remove the bushing easily and quickly, and for this purpose, as well as in order to hold it securely in its operative position, the lower end of the bushing is seated on a sheet metal washer I of frusto- 1 conical form whichJn turn, rests on an internal annular shoulder 8 formed in the bobbin, these parts assistin in guidin the end of the blade against the upper end of the bushing and holding it against ts seat is a split spring ring 9 which expands, due to its inherent resiliency, into engagement with the bore of the bobbin. The latter may be grooved, as shown at ill, to receive this member. I have-found, however, that this is not necessary with 'a rubber bushing and if it is dropped into the upper end of the bobbin, as

0 shown in Fig. 2, and the split rin 9 is pushed in against it, the ring will expand into such 'firm engagement with the bore of the bobbin that it is thereafter surprisingly difiicult to push the bushing out. In fact. it is almost impossible to 5 do so simply by pushing on the bushing. Apparently this is due to a reaction of the rubber on the split ring which increases the grip of the latter on the bobbin bore. This obviously is a very desirable condition since it avoids any danger of- 40 loosening the bushing due to its frictional contact with the top of the spindle blade as the bobbin is placed on the spindle. At the same time the spring can easily be removed by means of ahook *inserted in the top of the bobb1n,. or a split hook 45 may be used hr this purpose-having two hook shaped prongs directed away from each other and adapted to snap under the opposite sides of the vrin after being forced down through it. As soon as the ring is removed the bushing maybe shaken 50 out and replaced by a new one.

A constmction of this nature makes it entirely possible to utilize the high spindle speeds and the larger packages which are rapidly gaining favor without incurring the objections to both that have been described above. The simplicity of the mounting of the bushing and the ease with which'it may be secured in place or removed and replaced, when desired, is an important practical advantage.

This application is based on an improvement in the constmction shown in my pending application Ser. No. 235,295, filed October 15, 1938. Claims generic to the two constructions are presented in the earlier case, and the claims of the instant application are limited to. features not disclosed in the original case. While I have herein shown and described a typical embodiment of the invention, it will be understood that the invention is susceptible of embodiment in other forms without departing from the spirit or scope thereof.

Having thus described my invention, what I desire to claim as new is:

1. A bobbin for use inspinning, twisting, and similar machines, said bobbin comprising a tubular body adapted to be slipped on and oii a spindle in such a machine, a resilient bushing in the upper part of said body adapted to yieldingly center the upper portion of the bobbin on the spindle blade, means for holding said bushing in a fixed position longitudinally in said body includinga frusto-conical washer against which the lower end of said bushing bears, the smaller end of said washer being directed upwardly, and means in said bobbin against which the upper end of said bushing bears, said means being releasable to permit the removal of said bushing through the upper end of the bobbin.

2. A bobbin for use in spinning, twisting, and similar machines, said bobbin comprising a tubular body adapted to be slipped on and off a spindle in such a machine, a resilientbushing in the upper part oi! said body adapted to yieldingly center the upper portion of the bobbin on the spindle blade, said bobbin having an internal shoulder, a frusto-conical washer, the lower and larger end of which engages said shoulder while the smaller end'is directed upwardly, the lower end of said'bushing bearing on said washer, and a split spring ring in said bobbin bearing against the upper end of the bushing.

JOHN A. KENNEDY. 

